I have seen a great number of air-intakes for ventilation systems here in the US that all look alike: A duct protruding a wall; sometimes with a grille to keep debris out, sometimes cut at an angle or decorated to stand out as an architectural gesture. (FYI, the lip shown above in the image is the underside of an exterior metal window sill.)

Air Intake

Air Intake


During my visit to Germany I came across this intake, that also doubles as a filter for pollen and particles. I thought this was a neat idea and worth replicating, even if the design of the box could use a little bit of design attention. The filters in HRV or ERV machines are not really meant to take care of these pollutants and by the time they get to the equipment, they are already inside the duct-system. I have yet to locate a resource for such a product in the US—the model shown is made by a company named Paul in Germany. 

Filtered Air Intake

Filtered Air Intake


  • Russ Hellem says:

    I am a building science tech out of Montana and we specialize in HRV/ERV sales and installation. We routinely install intake filters on our systems to filter out pollen, dust and smoke (from forest fires). It consists of a 5″ deep can that allows for 2 2″ filters. The first is a particle filter and the second a charcoal filter during certain seasons.

    I have just completed a building for a long term investment property that I am in the process of running through the PHPP software. I believe it will be very close to the standard but we will see.

    I hope to make it in November.

    Russ Hellem

  • Tim, what did you end up doing at the Passive House in the Woods on this filtration issue?

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.